题目内容：

Who did the teacher_______the letter for the whole class?
A has write B has written C have write D having written
为什么选C?谢谢帮我分析!

优质解答

是应选C,给你简单说说：
大意：老师让谁为全班写信?
首先说明,这里have和write只是碰了一面而已（碰巧挨在一起）,无任何关系.
将原句还原成陈述语序：
The teacher had who write the letter for the whole class.
此处have 用做"have sb.（who) do sth."表示让某人做某事.
另外,for the whole class 改为 to the whole class也可,两种表达都讲的通.
这样一看,A B D都在误导你认为此处have（has)是完成式的标志,对吧.